This invention relates to a wheel for a motor vehicle having a rim spider with air openings and having a rim well connected with the rim spider, and a method of making such a wheel.
From German Patent Document DE 23 11 740, a vehicle wheel is known which consists of a ribbed rim spider which is provided with air openings, which is arranged inside a rim well which has both rim flanges. The rim spider is welded several times to the rim well on the inside and consists of a light-metal casting, the rim well being made of a light-metal sheet. Furthermore, vehicle wheels are known from U.S. Pat. No. 4,610,482 which are constructed in two parts, the rim well being connected on the inside of the rim spider in the area of the rim flange by means of welding.
It is an object of the present invention to provide a multi-part vehicle wheel which can be manufactured in a simple manner, which has a high stability while its weight is low, and which is constructed such that it can be connected in a simple manner and different connection processes can be used.
This object has been achieved according to the present invention by providing a wheel for a motor vehicle comprising at least two shell parts which form a rim spider, and a rim well connected with the rim spider, each of the rim spider and the rim well defining air openings, said at least two shell parts being connected with one another by at least one connection to form an axially inner wall, an axially outer wall, a plurality of hollow spokes which extend generally radially between adjacent of said air openings and which extend between at least one radially outer annulus and at least one radially inner annulus.
According to another preferred embodiment, a wheel for a motor vehicle is provided with a rim spider defining a plurality of air openings and with a rim well connected with the rim spider, wherein the wheel comprises at least two shell parts forming the rim well and the rim spider which each have an interior wall and an exterior wall, said shell parts forming a plurality of hollow spokes radially extending from adjacent air openings and defining an exterior annulus and an interior annulus, wherein said shell parts are connected with one another by means of at least one of welded connection and a threaded connection,
According to another preferred embodiment, a method for producing a wheel is provided comprising the steps of: forming a first shell part into a rim spider with an exterior ring web, boundary walls defining air openings and cylindrical receiving devices for wheel fastening bolts; forming a second shell part into a rim well with an exterior ring web, opening edges for air openings and pot-shaped bearings and a hub sleeve, subsequently assembling said first and second shell parts into a centered assembly by means of the mutually engaging portions, such that the edges of the of the wall sections in the rim spider rest on the interior edges of the air openings of the rim well, the hub sleeve is arranged in the exterior hub ring, the ring webs of the rim spider and of the rim well are situated directly opposite one another with their faces, and subsequently welding the mutually engaging portions of the two shell parts to connect the shell parts with one another.
The principal advantages achieved of the present invention are that the rim spider and the rim well each consist of one shell part which can be connected to one another in an assembled manner and hollow spokes are formed between the air openings of the shell parts. The shell parts may be manufactured separately from one another by different processes and from various materials so that, corresponding to the demands on the wheel, the material and the manufacturing process as well as the connecting process, for example, a welding process, can be freely selected.
The shell parts are each constructed with areas which supplement one another; that is, when the two shell parts are fitted together for being connected, these areas may act as so-called centerings with respect to one another. Thus, the rim spider has air openings which are formed by inwardly aligned boundary walls which, in the fitted-together condition of the shell parts, project into air openings of the rim well and can be connected to the opening edges of these air openings, in which case this may take place by way of a welding or a gluing process.
Furthermore, when the shell parts of the rim spider are fitted together with the rim well, cylindrical receiving devices of the rim spider are arranged in the pot-shaped bearings of the rim well. In addition, the exterior ring of the hub of the rim spider is held on the hub sleeve of the rim well. In the meeting exterior ring area of the two shell parts, a so-called continuous hump surface is formed by means of the ring webs on both rim parts.
The connecting of the two shell parts for forming the finished wheel takes place by means of a connection, by welding, gluing or processes with the same effect, preferably between the two ring webs, between the hub sleeve of the rim well and the exterior ring of the hub of the rim spider. In addition, another connection may take place between the boundary walls of the air openings in the rim spider with the opening edges in the rim well, which is usually the case.
According to one advantageous embodiment, the hub rings of the shell parts of the rim spider and of the rim well are fitted into one another for the connection so that an optimal centering of the two shell parts is ensured for the connection. Either the hub rings overlap completely so that a connection, for example, a welded connection, takes place on the interior supporting surface of the rim well or the interior hub ring ends approximately in the center of the exterior hub ring and the welded connection is then situated inside the exterior hub ring.
For the special design of the rim spokes and of the exterior annulus of the rim formed as a function thereof, the connection between ring webs of the rim well and of the rim spider can be designed in a variable manner, whereby a free-standing edge in an approximate Z-shape or in an approximate angular shape is obtained so that a well base rim can be produced which is distinguished by deep-lying rim spokes.
By means of the shell parts, particularly on the basis of the inwardly directed boundary walls of the air openings in connection with the opening edges of the air openings of the rim well, stability-increasing hollow spokes are formed between the air openings, which hollow spokes, in each case, lead on the end side into concentric annuli of the wheel and, in addition, these also have a stability-increasing effect. On the one hand, these annuli are formed between the upper boundary walls of the air openings and the ring webs as well as the lower boundary walls of the air openings around the hub sleeve.
Radially extending ribs, which have a stiffening effect, may be molded on inside the hollow spokes and are provided in the shell part of the rim spider as well as in the shell part of the rim well. The ribs arranged in the hollow spokes are preferably situated opposite one another and are constructed as half-ribs. Preferably they are arranged at a distance from one another in the center plane of the hollow spoke. The shell parts may be made of various materials, for example, of an aluminum alloy, a magnesium alloy or a titanium alloy, in which case the individual shell parts can be combined in the various materials. It is also possible to construct the shell parts of sheet metal, in the die-casting process or of a cast rolled material. A connection of the two shell parts may be carried out by means of a welding process, such as a fusion welding, a laser welding or an electron beam welding or by means of a gluing process.
These and other objects, features and advantages of the present invention will become more readily apparent from the following detailed description when taken in conjunction with the accompanying drawings.